The present invention relates to a semiconductor device manufactured through the use of a longitudinally extending tape-like carrier including a metallic layer secured on a flexible insulative layer, said insulative layer having centrally located longitudinally spaced apertures.
It has been proposed to provide a semiconductor device mounted on a flexible carrier for the sake of reduction of manufacturing cost and facilitating mass production. For example, U.S. Pat. No. 3,763,404, "SEMICONDUCTOR DEVICE AND MANUFACTURE THEREOF" to Alanson D. Aird shows a semiconductor device mounted on a flexible carrier.
In the prior art technique, the contact regions between lead patterns formed on a flexible film and metallic raised contacts or bumps provided on a semiconductor pellet have similar dimensions, without regard to the locations of the metallic contacts. However, the strength of bonded contacts between the lead patterns and the metallic raised contacts is not uniform because of the variation of the heat which is developed in the bonding tool as described hereinbelow.
A semiconductor pellet usually has gold-covered raised metallic contacts, e.g., bumps attached to electrically active regions of the semiconductor pellet. Tin plated copper leads formed on an insulating film are placed in abutment with the gold-covered raised metallic contacts. The tin plated copper leads are pressed against the gold surface portions of the gold-covered raised metallic contacts by the downward movement of a heatable bonding tip to affect the bonding of the gold-covered raised metallic contacts to the tin plated copper leads. Bonding is then achieved by applying a suitable electrical resistance heating current to the bonding tip. Since the heat temperature developed on the bonding tip is not uniform, the bonding strength between the gold-covered raised metallic contact and the tin plated copper lead is unavoidably varied to a degree depending on the various locations of the raised metallic contacts or bumps.